Source: ConocoPhillips.

Oil-stock dividends have been one of the great casualties of the oil-price downturn. The list of oil stocks that have cut or suspended dividend payments is growing by the day. In fact, given where prices are today, one high-yielding oil stock has already signaled that its dividend will likely come down next year.

Not all dividend payments are likely to be cut even if oil prices remains weak, however, as two other high yielders recently reiterated that their dividend payments aren't at risk of being cut, even if oil stays lower for longer. Here's a look at the two super-safe dividends, and the one that will likely not last all that much longer.

"The dividend is safe. Let me repeat that. The dividend is safe."
ConocoPhillips'
(COP 1.43%) CEO Ryan Lance pounded the table on the company's second-quarter conference call that its dividend is safe. In fact, just to reiterate the importance the company places on that payout, it recently increased it by $0.01 because, "we believe this was an important message for our shareholders," according to Lance.

Investors are still very worried about the payout, which is why the company's stock is currently yielding more than 6%. The reason for this concern is the fact that the company is overspending its cash flow as we can see on the following chart.

Source: ConocoPhillips Investor Presentation.

As that slide shows, throughout the first half of the year, ConocoPhillips needed to borrow $2.4 billion in debt to fund its capex plus dividends to overcome a shortfall in cash flow from operations. The company expects this outspend to narrow during the next two years as it has several major projects staring up that will lower capex spending and increase cash flow. In fact, its current plan has the company cash-flow neutral by 2017, even at current commodity prices, which is why the company firmly believes its dividend is safe.

Generating lots of excess cash flow
Suncor Energy
(SU 2.15%) is another company that firmly believes its dividend is safe. That's why, like ConocoPhillips, it recently increased its payout. However, the reason Suncor Energy was able to increase its dividend is more a function of the fact that it's actually generating a lot of excess cash flow as opposed to placing a high priority on the dividend.

Speaking of cash flow, so far this year, Suncor Energy has generated $700 million in free cash flow, even after spending billions of dollars on growth-focused capex. In fact, the company is generating so much free cash flow right now that it actually has enough after dividends and capex to restart its stock buyback program. Given its integrated asset base, Suncor Energy doesn't expect that its ability to generate excess cash flow will be affected by the current environment, which is why its dividend looks like a lock for the long term.

This one's probably not going to make it
While ConocoPhillips and Suncor Energy's dividends aren't going anywhere but up for the next few years, the same can't be said about Denbury Resources' (DNR) more than 7% dividend. As the following slide notes, the company's dividend philosophy is built upon maintaining a solid financial position whereby the company can fund the payout and capex with cash flow.

Source: Denbury Resources Investor Presentation.

That's not a problem for 2015, as the company's oil production is well hedged, enabling it to fund its capex of $550 million and dividend of $89 million, while still generating about $100 million in free cash flow. Its oil hedge position starts to drop off in the fourth quarter of this year as its hedged volumes will fall from 58,000 barrels per day in the third quarter to just 38,000 barrels per day. That rate holds steady throughout the first half of next year before falling off again to just 7,500 barrels per day by the third quarter of 2016. In other words, its exposure to the downside of commodity prices is going to increase during the next year.

With this in mind, Denbury Resources' CEO Phil Ryhoek warned investors at a recent conference that they are taking the dividend a quarter at a time right now. He said that: "We'll see where oil prices go, but to be honest, I don't know for sure what we'll do next year, it is something that we'll just have to evaluate. If prices stay really low there is a chance it gets reduced or adjusted."

He also said that, while the dividend is important, having a strong financial position is its priority. In other words, don't bank on Denbury Resources' current dividend rate to survive the downturn.

Investor takeaway
The plunge in the price of crude has hit oil-related dividends really hard, with several being cut. Another cut is looking likely by the day as Denbury Resources' dividend probably isn't going to make it through the downturn. There are still some companies that are making their dividends a priority, with ConocoPhillips and Suncor Energy topping that list, as both companies have strong balance sheets and more cash-flow clarity than their peers, which should keep their dividends safe for years.